/* Copyright (c) 2006, Jan Flora <janflora@diku.dk>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  - Neither the name of the University of Copenhagen nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
  @author Jan Flora <janflora@diku.dk>
*/

module FIFOQueueM
{
	provides
	{
		interface FIFOQueue;
	}
	uses 
	{
		interface Debug;
	}
}
implementation
{
	#define DBG_LEVEL 0
	#include "Debug.h"
	
	command result_t FIFOQueue.initQueue(FIFOQueue_t *theQueue, uint8_t **buffer, uint8_t size)
	{
		theQueue->buffer = buffer;
		theQueue->bufferHead = 0;
		theQueue->bufferCount = 0;
		theQueue->bufferSize = size;
		return SUCCESS;
	}
	
	async command result_t FIFOQueue.enqueue(FIFOQueue_t *theQueue, uint8_t *element)
	{
		if (theQueue->bufferCount == theQueue->bufferSize) {
			return FAIL;
		}
		theQueue->buffer[((theQueue->bufferHead+theQueue->bufferCount)%theQueue->bufferSize)] = element;
		theQueue->bufferCount++;
		return SUCCESS;
	}
	
	async command result_t FIFOQueue.dequeue(FIFOQueue_t *theQueue, uint8_t **element)
	{
		if (!theQueue->bufferCount) {
			return FAIL;
		}
		*element = theQueue->buffer[theQueue->bufferHead];
		theQueue->bufferHead = (theQueue->bufferHead+1)%theQueue->bufferSize;
		theQueue->bufferCount--;
		return SUCCESS;
	}
	
	async command bool FIFOQueue.isFull(FIFOQueue_t *theQueue)
	{
		if (theQueue->bufferCount == theQueue->bufferSize) {
			return TRUE;
		}
		return FALSE;
	}
	
	async command bool FIFOQueue.isEmpty(FIFOQueue_t *theQueue)
	{
		if (theQueue->bufferCount) {
			return FALSE;
		}
		return TRUE;
	}
	
	async command uint8_t FIFOQueue.elementCount(FIFOQueue_t *theQueue)
	{
		return theQueue->bufferCount;
	}
}
